back to 2025.07.06 K0DV beam troubleshoot

2 evaluation on 2025.07.07:


I stopped back over the next day with my Spark and good camera, to more closely inspect the beam and coax.
We didn't get a good look yesterday due to only having modest binoculars and cell phone cameras, and having
to look at things only from below.

The spark got good pictures and some video, and I was also able to obtain some great pictures with my digital
camera. It's a Nikon Coolpix P510, with a 42x optical zoom, so it can really reach out and touch someone.
Honestly, pictures from the Spark from 10ft away were about equal in quality to pictures taken from the ground
(60ft away) with the Nikon.

The pictures answered our questions though. With extreme close-ups, shots from the side and above, and not
having the sky as a background showed what appears to be the balun broke loose from its mount and broke the
braid side connection to the lower boom. There's a nylon "beaver tail" that sticks about 5 inches out the
front of the beam, that the balun cylinder was wire-tied to. I don't have any good pictures of it during the
install, but IIRC the balun was tied heavily to the beaver tail. (lots of wire ties? lots of electric tape?)
But whatever it was, it failed. Not sure if it was due to UV, or going around sharp edges on the beaver tail
or what did it. But we need to fix the thing at the very front of the beam, something like 15 feet out from
the tower. Looking at the beaver tail now, that nylon has sharp edges and it might have just sheared off the
attachment. (bad design)

Now that we know what's wrong, we get to think of an approach for repairing it. It took Jason Joens all day
(with a big ground crew) to get that monster up there, so taking it down for repair is probably impractical.
Doug's driveway slab is on a steep hill with what looks like a 15 foot drop on one end, so it's impossible to
bring a heavy bucket truck up to the tower. The only alternative I can think of is to support the antenna
from the mast pole that sticks up above it, unbuckle the mast/tower bracket, and tilt the front of the beam
down so the beam is parallel to the tower. This will bring the balun to the tower where we can access it.

This wouldn't be a trivial process. The beam is very heavy to begin with, and even if it was balanced
perfectly at the bracket, it's lost an element out near the front, which will make it back-heavy, and want to
raise the front instead of lowering it. So it's going to have some "fight" in it, and will require there to
be two climbers up there to man-handle it.



deer


Nikon media


Spark media


zoomed detail pics



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